In recent years, mobile terminals such as mobile phones are equipped with advanced functions such as a function of receiving “One-Seg” (one-segment television) broadcasting. As a result, mobile terminals having such a complicated shape that they can be used with the screen being in a landscape position in addition to in the conventional portrait position have come into use. In such mobile terminals, the restrictions on the positional relation between the speaker and the receiver have become stricter. As a result, mobile terminals in which receivers are disposed in a plurality of places as well as mobile terminals in which the receiver and the speaker are disposed adjacent to each other so that they are shared to achieve the miniaturization have come onto the market.
As for the mobile terminals in which the receiver and the speaker are disposed adjacent to each other among these mobile terminals, there are folding-type mobile communication terminals in which consideration is given to lessening the discomfort to users (for example, see Patent literature 1). The invention disclosed in Patent literature 1 relates to a mobile communication terminal. This mobile communication terminal includes a receiver for a telephone call, a speaker for producing a ringtone, means for setting the volume of a ringtone, means for determining the volume of a ringtone, means for processing a ringtone, and means for detecting the opening/closing of folding housings. The receiver for a telephone call is disposed in one housing of the folding housings. The speaker for producing a ringtone is disposed adjacent to the receiver for a telephone call. The means for setting the volume of a ringtone sets the volume of a ringtone according to user setting. The means for determining the volume of a ringtone determines the volume of a ringtone according to the set volume of a ringtone. The means for processing a ringtone processes the volume of a ringtone to be produced from the speaker for producing a ringtone based on an adjusted volume. The means for determining the volume of a ringtone determines the adjusted volume according to the detection result of the opening/closing detection means.
It is stated in Patent literature 1 that since the amplification process is performed so as to obtain only the volume specified by the adjusted volume, the necessary amount of the consumed power is small. Patent literatures 2 and 3 also disclose techniques related to that disclosed in Patent literature 1. The invention disclosed in Patent literature 2 relates to a mobile device. This mobile device includes a first housing including a first operation unit, a second housing including a display unit, a third housing, and a connection mechanism to connect the first, second, and third housings to each other. The connection mechanism connects the housings in such a manner that second housing can freely move from a first position at which the silhouette of the second housing conforms to that of the first housing to a second position and to a third position. Further, the connection mechanism connects the housings in an integrated fashion so that the silhouette of the second housing conforms to those of the first and third housings in the first position. Further, the connection mechanism connects the housings in such a manner that when the second housing is moved from the first position to the second position, it restricts the movement of the third housing such that the amount of the movement of the third housing resulting from the movement of the second housing is zero or smaller than that of the second housing so that the third housing is exposed. Further, when the second housing is moved from the first position to the third position, it restricts the movement of the third housing such that the amount of the movement of the third housing resulting from the movement of the second housing is equal to or smaller than that of the second housing so that the first operation unit is exposed and thereby brought into an operable state.
It is stated in Patent literature 2 that when the display of the mobile device is in the portrait position, an operation member suitable for the portrait position is exposed, whereas when the display is in the landscape position, an operation member suitable for the landscape position is exposed. As a result, it is possible to provide the mobile device that can be easily operated by a user.
The invention disclosed in Patent literature 3 relates to a method of controlling the ringtone volume of a mobile phone. In this ringtone volume control method for a mobile phone, it is determined whether the number of ringtones is greater or smaller than a set number. Then, when the number of ringtones is smaller than or equal to the set number, the volume of a ringtone is set to a fixed value, whereas when the number of ringtones is greater than the set number, the volume of a ringtone is set to an arbitrary variable value.
According to the invention disclosed in Patent literature 3, when the number of ringtones detected by ringtone detection means is smaller than or equal to the set number, a ringtone having a predetermined comparatively small volume is produced, whereas when the detected number of ringtones exceeds the set number, a ringtone having a comparatively large volume that is set in advance by a user is produced. Accordingly, when the mobile phone receives an incoming call in a state where the user puts the mobile phone near his/her ear, the user can perceive the incoming call by a comparatively small ringtone, thereby preventing the damage to the ear. On the other hand, it is stated in Patent literature 3 that when the mobile phone detects an incoming call in a noisy place such as on the street, the user can perceive the incoming call in a shorter time than when an incoming call is received by using a conventional ringtone volume control method for a mobile phone because the ringtone is comparatively large after the set number of ringtones.
In addition to these mobile terminals, other mobile terminals including a mobile terminal in which the volume of the speaker at the time of receiving an incoming call is reduced in the opened state and a mobile terminal in which a vibration is used instead of the ringtone have been also proposed.
Note that in a folding-type mobile terminal, the opened state can be regarded as the used state. However, in the case of an integral-type mobile terminal, the user cannot determine that the mobile terminal is in an unused state by using the method like this. That is, the above-described method cannot be simply applied. Therefore, as for the integral-type mobile terminal, mobile terminals in which the volume is reduced for a predetermined period have come onto the market.